With the rapid development of a mobile terminal such as a mobile phone, people pay more attention to an appearance of the mobile phone, and in particular, to a material of the mobile phone. A plastic housing is generally used for a common mobile phone, for example, Polycarbonate (PC), Acrylonitrile Butadiene Styrene (ABS), or ABS+PC. In recent two years, a mobile phone made of a metal material has gradually drawn people's attention. The mobile phone made of a metal material is fashionable and has a fine texture, a metal housing is more durable than a plastic housing, and heat conductivity of metal is better; a long-time operation does not cause overheating of the mobile phone, which extends a service life of the mobile phone. These advantages interest people in purchase of a mobile phone made of a metal material.
A demand stimulates a market, and in a current industry, a design difficulty of a mobile phone that has a metal-material housing lies in an antenna. For a common antenna, a metal housing shields antenna radiation, and therefore, no signal is available for the mobile phone or a call drop occurs. In the prior art, a solution is removing metal within an antenna area, and the mobile phone uses a regular Inverted F Antenna (IFA)/Planar Inverted F Antenna (PIFA)/Loop antenna as a radiator, instead of using a metal housing as a radiator; therefore, the metal housing within the antenna area of the mobile phone needs to be replaced with a plastic housing. In the technical solution, a plastic housing needs to be used, and in terms of appearance, metal is in the middle and plastic is at the two ends, which has a splicing effect; in addition, there is no sense of an all-metal housing. If a plastic material that has a metal spraying color is used as a replacement, an overall effect of a product is damaged.
In the prior art, there is also a solution in which dual antennas are used for switching to avoid impact on an antenna caused by a metal housing. The antenna is disposed on an external face of the housing of the mobile phone, and when one antenna is held by a hand during a call, a detection apparatus is started, and a signal is switched to the other antenna; therefore, in the antenna solution, multiple antennas need to be used and costs are relatively high. For an Orthogonal Frequency Division Multiplexing (OFDM) multi-carrier aggregation technology in a 4G Long Term Evolution (LTE) system, the antenna switching solution is not applicable, because a signal carrier is equivalent to serial transmission, and an antenna may be switched for serial transmission; but LTE OFDM is equivalent to multi-carrier parallel transmission, and consequently the antenna switching solution is not applicable.
In the prior art, an active-antenna solution may also be used, that is, a metal housing is involved in radiation as a part of an antenna. In a switch switching solution, antenna matching is dynamically switched, to achieve an objective of implementing communication by an antenna in a head-hand mode (that is, a state in which a head and a hand of a person use a mobile phone is simulated). Although the solution in the prior art can be used in an LTE solution, components such as a switch and an adjustable capacitor need to be introduced; therefore, application costs are quite high.